Weird water pressure issue in house... tenants moving in today, any ideas? (w/pics)

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tireshark

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Ok, so for the past two weeks i have been getting the place in shape and noticed that all the faucets/toilets had low water pressure... i just thought that the water main at the street wasn't open all the way and didn't mess with it. Get renters, and finally decide to go to the street to open it up all the way and i discovered that it is already open.

Here are some things i have observed:



  • the dial isn't spinning when the water is off, so no leaks anywhere.

  • the kitchen sink, bathroom sink, tub, and toilet are all exhibiting only a low-medium water flow (toilet takes over 2 minutes to refill)

  • when i first turn on any of the faucets, i will get a normal high pressure flow for about 1 second, and then it drops as the built up pressure drops

  • the washing machine cold water supply (2nd exit point in the house off of the main line) appears to have a normal high pressure flow.
  • an outside spigot (1st exit point in the house off the main line), which branches off a few feet BEFORE the washing machine cold water supply, is exhibiting the low pressure issue
  • the washing machine hot water supply appears to have normal high pressure

I'm stumped. Normal high pressure at the washing machine outlets indicate that the pressure is ok coming from the street. A second of normal pressure at the sink faucets before the pressure drops indicates that the lines aren't built up with deposits (otherwise it wouldn't flow with normal pressure for that first second, right?).

The most puzzling to me is why the WM cold outlet flows normal high pressure, but the spigot that splits off a few feet BEFORE it flows low pressure. If high pressure is going to the WM, it should be going to that spigot... i mean there is a shut off valve on the spigot branch, that i suppose could be bad (wouldn't think it likely but i guess its possible) but then whats the deal with the rest of the house?

Thanks for any advice!

Pictures:

main line with spigot branch and shut off valve

main line entering house and washing machine cold water supply

Videos:

Normal high pressure at washing machine outlets


Flow at kitchen sink (two turns)


Flow at tub


Flow at bathroom sink (two turns)
 
Last edited:
how long did the house set before you started working on it? is the pressure lose just on the cold side? does your house have a regulator? what kind of shut-off valve do you have at the house? i am not talking in the meter box. is there a shut off at the house
 
The house had only sat unused for a few days. The pressure loss is on the cold and hot side. There is no shut off valve at the house (that i am aware of), only at the curbside meter box which i have access to.

In the first picture there is a pressure reducing valve visible... is that what you are referring to when you asked about a regulator? I didnt know what that thing was until about 5 minutes ago, and it sounds like that might be where the problem lies. It is a threaded junction, so it should be easy to replace.

One thing that still puzzles me: if the PRV is bad, why would the washing machine outlets still have good pressure on them?

Regardless, it is looking like i probably need to replace it.

Thanks for your input!
 
Do you have any filtration? Softeners and those useless inline filters can plug causing the problem your having.
 
try taking the supply lines off the faucets you are having the problem with which would be your bathroom and kitchen sink. see if you have good pressure at the supply lines. if you do then you know it is the faucet. that regulator is an old watts reg. it probably would not be a bad idea to install a new one. before you remove the supply lines to the faucets remove the areators and see if they are clogged. they are the screens on the faucet where the water comes out
 
Journeyman, correct me if im wrong, but wouldn't the initial surge of high pressure (that you can see in the sink videos above) indicate that the faucets/aerators (and maybe even the lines) are ok?
 
Good news, turns out all i needed to do was adjust the PRV and it cranked the pressure up where it should be. Easy fix. Thanks for the help everyone.
 

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